NGINX: upstream timed out (110: Connection timed out) while reading response header from upstream

Question

I have Puma running as the upstream app server and Riak as my background db cluster. When I send a request that map-reduces a chunk of data for about 25K users and returns i

Answer 1

First figure out which upstream is slowing by consulting the nginx error log file and adjust the read time out accordingly in my case it was fastCGI

2017/09/27 13:34:03 [error] 16559#16559: *14381 upstream timed out (110: Connection timed out) while reading response header from upstream, client:xxxxxxxxxxxxxxxxxxxxxxxxx", upstream: "fastcgi://unix:/var/run/php/php5.6-fpm.sock", host: "xxxxxxxxxxxxxxx", referrer: "xxxxxxxxxxxxxxxxxxxx"

So i have to adjust the fastcgi_read_timeout in my server configuration

 location ~ \.php$ {
     fastcgi_read_timeout 240;
     ...
 }

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